Focused Assessment of State-of-the-Art CFD Capabilities for Prediction of Subsonic Fixed Wing Aircraft Aerodynamics

Several recent workshops and studies are used to make an assessment of the current status of CFD for subsonic fixed wing aerodynamics. Uncertainty quantification plays a significant role in the assessment, so terms associated with verification and validation are given and some methodology and research areas are highlighted. For high-subsonic-speed cruise through buffet onset, the series of drag prediction workshops and NASA/Boeing buffet onset studies are described. For low-speed flow control for high lift, a circulation control workshop and a synthetic jet flow control workshop are described. Along with a few specific recommendations, gaps and needs identified through the workshops and studies are used to develop a list of broad recommendations to improve CFD capabilities and processes for this discipline in the future

Building nursing and midwifery leadership capacity in the Pacific

© 2016 International Council of Nurses Aim: The Australian Award Fellowship Program aimed to strengthen nursing and midwifery leadership and capacity in developing countries in the Pacific. Background: It is necessary to build an optimal global health workforce, and leadership and mentorship are central to this need. This is especially important in small island states such as the Pacific who have limited capacity and resources. Introduction: This health system strengthening program addressed quality improvement in education, through the mentorship of potential nursing and midwifery leaders in the South Pacific Region. Methods: Program participants between 2013 and 2015 were interviewed. Data were audio-taped, transcribed and analysed thematically using an inductive process. Results: Thirty-four nurses and midwives from 12 countries participated. There were four main themes arising from the data which were: having a country-wide objective, learning how to be a leader, negotiating barriers and having effective mentorship. Discussion: Our study showed that participants deemed their mentorship from country leaders highly valuable in relation to completing their projects, networking and role modelling. Similar projects are described. Limitations: The limitation of this study was its small size. There is a need to continue to build the momentum of the program and Fellows in each country in order to build regional networks. Conclusions and implications for nursing and midwifery: The Program has provided beneficial leadership education and mentorship for nurses and midwives from Pacific countries. It has provided a platform to develop quality improvement projects in line with national priorities. Implications for health policy: Global aid programs and the recipients of the program would benefit from comparable health strengthening approaches to nursing and midwifery in similar developing countries

Oxygen consumption dynamics in steady-state tumour models

Oxygen levels in cancerous tissue can have a significant effect on treatment response: hypoxic tissue is both more radioresistant and more chemoresistant than well-oxygenated tissue. While recent advances in medical imaging have facilitated real-time observation of macroscopic oxygenation, the underlying physics limits the resolution to the millimetre domain, whereas oxygen tension varies over a micrometre scale. If the distribution of oxygen in the tumour micro-environment can be accurately estimated, then the effect of potential dose escalation to these hypoxic regions could be better modelled, allowing more realistic simulation of biologically adaptive treatments. Reaction-diffusion models are commonly used for modelling oxygen dynamics, with a variety of functional forms assumed for the dependence of oxygen consumption rate (OCR) on cellular status and local oxygen availability. In this work, we examine reaction-diffusion models of oxygen consumption in spherically and cylindrically symmetric geometries. We consider two different descriptions of oxygen consumption: one in which the rate of consumption is constant and one in which it varies with oxygen tension in a hyperbolic manner. In each case, we derive analytic approximations to the steady-state oxygen distribution, which are shown to closely match the numerical solutions of the equations and accurately predict the extent to which oxygen can diffuse. The derived expressions relate the limit to which oxygen can diffuse into a tissue to the OCR of that tissue. We also demonstrate that differences between these functional forms are likely to be negligible within the range of literature estimates of the hyperbolic oxygen constant, suggesting that the constant consumption rate approximation suffices for modelling oxygen dynamics for most values of OCR. These approximations also allow the rapid identification of situations where hyperbolic consumption forms can result in significant differences from constant consumption rate models, and so can reduce the computational workload associated with numerical solutions, by estimating both the oxygen diffusion distances and resultant oxygen profile. Such analysis may be useful for parameter fitting in large imaging datasets and histological sections, and allows easy quantification of projected differences between functional forms of OCR

Qualitative evaluation of a public-private partnership for reproductive health training in Papua New Guinea

© 2018 Thiessen J, Bagoi A, Homer C, Rumsey M. Introduction: The recent policy environment in both Papua New Guinea and Australia for partnering with private entities to address health issues has led to a public-private partnership (PPP) between the National Department of Health in Papua New Guinea, the Australian Government and the Oil Search Foundation. A reproductive health training unit was formed to provide health worker training in essential obstetric care and emergency obstetric care. This article provides a qualitative evaluation of the PPP, looking at facilitating features and barriers to the PPP's target of improving the competence of frontline health workers in obstetric care service provision in Papua New Guinea. Method: A qualitative methodology gathered data since the PPP's inception in 2012. A dataset of 85 interviews with partners and relevant stakeholders from across Papua New Guinea was analysed using thematic analysis. Results: Themes of facilitating features of the PPP were (1) understanding and agreeing with the national plan for PPPs and maternal and child health; (2) having strong champions, strong relationships and a formal decision-making body; and (3) creating autonomy and branding. Themes outlining the barriers to the PPP's effectiveness were (1) lacking governance framework creating confusion in decision making and roles and responsibilities; (2) differing institutional cultures and ownership struggles; and (3) lacking capacity within the institutes themselves, particularly the National Department of Health. Conclusion: The findings of this service provision case study confirm what has been found in other infrastructure-led PPPs. Further research into how to overcome power imbalances between partners in a PPP as well as setting up a governance framework in a dynamic environment could inform this growing area of collaboration between the private and public sectors

Finite Element Flow Simulations of the EUROLIFT DLR-F11 High Lift Configuration

This paper presents flow simulation results of the EUROLIFT DLR-F11 multi-element wing configuration, obtained with a highly scalable finite element solver, PHASTA. This work was accomplished as a part of the 2nd high lift prediction workshop. In-house meshes were constructed with increasing mesh density for analysis. A solution adaptive approach was used as an alternative and its effectiveness was studied by comparing its results with the ones obtained with other meshes. Comparisons between the numerical solution obtained with unsteady RANS turbulence model and available experimental results are provided for verification and discussion. Based on the observations, future direction for adaptive research and simulations with higher fidelity turbulence models is outlined.Comment: 52nd Aerospace Sciences Meetin

FUN3D and CFL3D Computations for the First High Lift Prediction Workshop

Two Reynolds-averaged Navier-Stokes codes were used to compute flow over the NASA Trapezoidal Wing at high lift conditions for the 1st AIAA CFD High Lift Prediction Workshop, held in Chicago in June 2010. The unstructured-grid code FUN3D and the structured-grid code CFL3D were applied to several different grid systems. The effects of code, grid system, turbulence model, viscous term treatment, and brackets were studied. The SST model on this configuration predicted lower lift than the Spalart-Allmaras model at high angles of attack; the Spalart-Allmaras model agreed better with experiment. Neglecting viscous cross-derivative terms caused poorer prediction in the wing tip vortex region. Output-based grid adaptation was applied to the unstructured-grid solutions. The adapted grids better resolved wake structures and reduced flap flow separation, which was also observed in uniform grid refinement studies. Limitations of the adaptation method as well as areas for future improvement were identified

Arbitrary Steady-State Solutions with the K-epsilon Model

Widely-used forms of the K-epsilon turbulence model are shown to yield arbitrary steady-state converged solutions that are highly dependent on numerical considerations such as initial conditions and solution procedure. These solutions contain pseudo-laminar regions of varying size. By applying a nullcline analysis to the equation set, it is possible to clearly demonstrate the reasons for the anomalous behavior. In summary, the degenerate solution acts as a stable fixed point under certain conditions, causing the numerical method to converge there. The analysis also suggests a methodology for preventing the anomalous behavior in steady-state computations

Attitude Determination from Single-Antenna Carrier-Phase Measurements

A model of carrier phase measurement (as carried out by a satellite navigation receiver) is formulated based on electromagnetic theory. The model shows that the phase of the open-circuit voltage induced in the receiver antenna with respect to a local oscillator (in the receiver) depends on the relative orientation of the receiving and transmitting antennas. The model shows that using a {\it single} receiving antenna, and making carrier phase measurements to seven satellites, the 3-axis attitude of a user platform (in addition to its position and time) can be computed relative to an initial point. This measurement model can also be used to create high-fidelity satellite signal simulators that take into account the effect of platform rotation as well as translation.Comment: 12 pages, and one figure. Published in J. Appl. Phys. vol. 91, No. 7, April 1, 200

Pre-operative experiences and post-operative benefits of ptosis surgery: A qualitative study

© 2017 Taylor & Francis. This qualitative study sought to explore the experiences of patients who had undergone successful ptosis correction surgery. Participants were recruited from Bristol Eye Hospital. Nine participants were interviewed using a semi-structured interview schedule and open ended questions. Data were analysed using inductive thematic analysis. Four major themes were identified from patient accounts. Patients described the psychosocial and functional difficulties they experienced living with ptosis, and the subsequent benefits of surgery. Patients reported experiencing appearance related anxiety pre-operatively due to their condition and engaging in behaviours to avoid social encounters. Gender differences were noted in the internalization of perceived negative reactions from others, with men describing fewer adverse impacts. Patients described perceived barriers to seeking surgery including a lack of awareness of ptosis as a treatable condition, the perception that being concerned with their appearance could be seen as vain and the view that ptosis surgery is synonymous with cosmetic surgery. Following successful surgery patients outlined positive impacts on their vision, appearance and psychosocial well-being after successful surgery. This qualitative study highlights the complexities of the factors and processes contributing to the psychosocial impacts of ptosis and the potential benefits of surgery and/or psychosocial support. An increased awareness amongst people with ptosis of the potential positive impacts of surgery and an enhanced understanding of the reasons why patients may not seek treatment amongst health care professionals are likely to benefit this often overlooked patient group